diff --git a/.github/workflows/ci-testing.yml b/.github/workflows/ci-testing.yml
index b6f66b3c..ca415ecc 100644
--- a/.github/workflows/ci-testing.yml
+++ b/.github/workflows/ci-testing.yml
@@ -19,11 +19,10 @@ jobs:
       fail-fast: false
       matrix:
         os: ["ubuntu-22.04", "macos-14", "windows-2022"]
-        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
+        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13", "3.14"]
         exclude:
           - { os: "windows-2022", python-version: "3.13" }
-          - { os: "macos-14", python-version: "3.12" }
-          - { os: "macos-14", python-version: "3.13" }
+          - { os: "windows-2022", python-version: "3.14" }
 
     # Timeout: https://stackoverflow.com/a/59076067/4521646
     timeout-minutes: 60
diff --git a/setup.py b/setup.py
index 5d92d9ed..e320d57d 100644
--- a/setup.py
+++ b/setup.py
@@ -99,5 +99,7 @@ def _prepare_extras(requirements_dir: str = _PATH_REQUIRES, skip_files: tuple =
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
+        "Programming Language :: Python :: 3.13",
+        "Programming Language :: Python :: 3.14",
     ],
 )
diff --git a/src/litdata/streaming/dataloader.py b/src/litdata/streaming/dataloader.py
index 27205cea..fa47b346 100644
--- a/src/litdata/streaming/dataloader.py
+++ b/src/litdata/streaming/dataloader.py
@@ -624,7 +624,7 @@ def __init__(
         self._num_samples_yielded_wrapper: dict[int, list[int]] = {}
         self._num_cycles: dict[int, list[int]] = {}
         self.rng_state: Optional[Any] = None
-        self._worker_idx = cycle(list(range(self.num_workers if self.num_workers > 0 else 1)))
+        self._worker_idx: Optional[Any] = None  # Lazily initialized in __iter__
         self._worker_idx_iter: Optional[Any] = None
         self._latest_worker_idx = 0
         self.restore = False
@@ -767,6 +767,9 @@ def load_state_dict(self, obj: dict[str, Any]) -> None:
 
         # Used to restart on the next DataLoader worker from the previous run.
         self._latest_worker_idx = obj["latest_worker_idx"] + 1
+        # Initialize _worker_idx if not already set (e.g., when loading state before first iteration)
+        if self._worker_idx is None:
+            self._worker_idx = cycle(list(range(self.num_workers if self.num_workers > 0 else 1)))
         self._worker_idx_iter = iter(self._worker_idx)
         for _ in range(self._latest_worker_idx):
             next(self._worker_idx_iter)